Nationwide Building Society has refused to take part in an independent assessment of which financial products are good for customers.

The UK’s biggest building society chose not to hand over information to the Fairbanking Foundation, a charity that awards ratings for products including savings accounts and credit cards from across the financial services industry that it deems to be in customers’ best interests.

Nationwide told the foundation that it had “other priorities” and therefore could not participate, but the organisation rated Nationwide anyway. The mutual ranked at the low end of its list of savings products and came out in